Humidifier



R. L. DUNN HUMIDIFIER Oct. 1, 1963 2 Sheets-Sheet 1 Filed March 30, 1961"IRWIN! Illlllillll INVENTOR. Z4. Dd/v/V ATTOE/VEY! R. L. DUNNHUMIDIFIER Oct. 1, 1963 2 Sheets-Sheet 2 INVENTOR. A. pdA/A/ AT 7' GENEY5 Filed March 30, 1961 United States Patent 3,105,360 HUMlDiFER RobertLyle Dunn, 104 N Marrietta Sh, Verona, Wis. Filed Mar. 3%, 1961, Ser.No. 99,627 3 Claims. (Q. 261-70) This invention relates to humidifiersof the type which are located, for example, in the air stream beingdelivered by a warm air furnace.

Prior art humidifiers which utilize a plurality of moisture absorbent,evaporator plates in an air stream have not been entirely satisfactory,because of the manner in which the supply of water is fed to the plates.More particularly, these plates would periodically become dry, at leastin part, which periodic and repeated drying of the absorbent plateswould cause an eventual build up of precipitated lime thereon, whichwould reduce their capillary action.

Accordingly, the present invention provides a humidifier of the typehaving a plurality of moisture absorbent plates in the form of sheets offlexible material in which the moisture is supplied in such a way thatcomplete saturation of the plates is insured and drying of the sheets,even partially, is prevented. As a result, lime is prevented from beingdeposited on the sheets and a particularly efficient humidifier isprovided. More particularly, the water is supplied to the upper portion,such as the upper edge, of vertically disposed sheets, which water thenflows and is drawn by capillary action downwardly and across the entiresurface of the sheets. The excess water then collects in a pan extendingacross the bottom of the sheets and in which pan the bottom of each ofthe sheets is located. When the level in this collecting pan reaches apredetermined height, the supply of water is positively shut off andcapillary action of the sheets continues to keep them wet by drawing thewater back upwardly from the pan. The action is such that moisture issupplied to the sheets from both the upper and lower edges thereof. Thedownwardly flowing water in effect periodically washes the sheets freeof any foreign debris.

Another problem in humidifiers of this general character arises inconnection with the deposit of lime on various moving parts of themechanism. This lime precipitation and accumulation occurs particularlywhen the water is above a certain temperature and on those parts overwhich a large volume of water flows. Nevertheless, it is desirable toinstall the humidifier in the warm air duct rather than the cold airduct because of the greater ability of warm air to pick up moisture.Float operated needle type valves for gradually changing the water flowrate have been used in some prior art humidifiers, and this type ofvalve mechanism is particularly susceptible to malfunction due to thislime build up on and between the movable parts.

It is therefore another object of the present invention to provide ahumidifier which overcomes the above difiiculties. More particularly,the improved device utilizes a float mechanism for actuating a positiveon or oil water supply valve, which mechanism is located outside of thewarm air duct and in a water chamber wherein water circulation andintermingling with water in the main collecting pan does not take placeto any appreciable extent. The float device is not located in thecontinually changing and warm water, but instead is isolated therefrom,except for a small water communication for actuating the float inaccordance with the water level in the collecting pan. As a result ofthe above arrangement, the water which operates the float remainsessentially the same which results in substantial elimination of limeprecipitation on any moving parts.

Another and more specific aspect of the present inven- 2 tion provides avalve actuating mechanism of the above type which utilizes a positiveon-off type of water supply valve which can be remotely located from theremainder of the humidifier unit. The valve is thereby not subjected tomalfunctioning due to build up of lime deposits thereon, as in valves ofthe type which gradually change the flow rate, and the water supply iseither fully on or completely closed. I

With the above arrangement, only the precise amount of water necessaryis required and an overflowing of excess water is not necessary formaintaining the sheets in a completely saturated condition.

Still another object of the present invention is to provide a moistureabsorbing sheet assembly which can be readily removed and replaced inthe air duct for complete and easy periodic cleaning of the sheetassembly.

It is still another and important object of the present invention toprovide a humidifier of the above type which is incorporated in anintegral duct unit for ready application between the warm air plenum andthe cold air return plenum of a forced, Warm air furnace. In thismanner, a portion of the Warm air being delivered by the furnace isdiverted to the cold air plenum after passing through the humidifier.These humidifier units can be readily installed in existing heatingsystems.

These and other objects and advantages of the present invention willappear as this disclosure progresses, reference being had to theaccompanying drawings, in which:

'FIGURE 1 is a perspective view of a humidifier made in accordance withthe present invention, and as applied between the warm and cold airplenum chambers of a forced, warm air furnace;

FIGURE 2 is a front elevational view of the device shown in FIGURE 1,the duct cover being removed for clarity;

FIGURE 3 is a horizontal, sectional view taken generally along line 3-3in FIGURE 2.;

FIGURE 4 is a vertical sectional view taken through the sheet assemblyalong line 4-4 in FiGURE 3;

FIGURE 5 is a sectional view taken along line 55 in FIGURE 4; and

FIGURE 6 is a front elevational view of the operating means shown inFIGURE 1, but on an enlarged scale, but with parts shown in section.

Referring in greater detail to the drawings, panticu-lan ly FIGURE 1,the humidifier unit H is shown as connected between the warm air plenumchamber W and the cold air return chamber R of a conventional forced,warm air furnace F. It should be understood, however, that the inventionis not limited to use in such an installation but can also be used inother air conveying ducts, such as, for example, in one which dischargesdirectly into a large area to be humidified and/or heated.

The unit as shown for illustrative purposes in the drawings comprises agenerally rectangular duct D, in cross section, which conducts air inthe direction of the arrow, more specifically, from the warm air plenumto the cold air return plenum. This duct may be mounted in anyconvenient location, that is, on either side of the furnace, and has aseries of flanges 1 around its inlet opening and -a series of flanges 2around its outlet opening whereby the duct may be easily attached to theplenum chambers in any well-known and suitable manner as by screws 3.Thus, the duct places the Warm air plenum in communication with the coldair plenum and a portion of the warm air is diverted throughout thehumidifier and back to the cold air return plenum.

:The humidifier assembly also includes the evaporator plate assembly PAwhich is inserted in the duct through the door 4 and is of such size asto substantially extend across the cross-sectional area of the duct. Awater supply manifold SM is located transversely across the top side ofthe duct and by means of which water is supplied evenly across theentire width of the sheet assembly PA, as will more fully appear.

A float chamber PC is secured to the outside of the duct D and is incommunication via conduit C with the collecting pan 5 which forms thebottom of the sheet assembly. An electrical, mercury-type switch S ispivotally mounted at 6 in a housing 7 which is secured to the outside ofthe duct and immediately above the float chamber so as to be actuated bythe vertically shiftable float 81ocated in the float chamber. When theswitch S is in the position shown by full lines in FIGURE 6, the circuitis closed between the electric wires 9 and 16. The switch S is limitedin its downward swinging by a stop 11 on the housing 7. When the float 3rises to the dotted line posi tion shown in FIGURE 6, the switch istilted to the dotted line position to open the circuit and de-energizethe solenoid operated water valve to be described. Electric wires 14extend from the mercury switch to the solenoid operated on-ofl" watersupply valve 15, and supply lines L1 and L2 lead to the electric powersource (not shown).

The water supply valve may be located at any convenient location andremote from the rest of the unit and has been shown here for purposes ofillustration as being mounted on a water pipe P from which it receiveswater. A water supply conduit 16 leads from the discharge side of thevalve to the water supply manifold SM.

Then general operation of the unit is that when the water in thecollecting pan 5 of the sheet assembly reaches a predetermined level,the water in the float chamber is at a corresponding level because ofthe connecting conduit C, and the float 8 has then risen to a pointwhere it tips the pivotally mounted mercury switch to thereby break thecircuit and cause de-energization of the solenoid 18. The normallyclosed water supply valve thereby closes, thus stopping the flow ofwater to the supply manifold SM. Conversely, when the water supply inthe collecting pan drops below the predetermined level, the mercuryswitch is permitted, under the influence of gravity, to fall back to itsoriginal position, thereby causing energiza-tion of the solenoid andconsequent opening of the water supply valve. Water then flows to thesupply manifold until a suflicient amount has filled the collecting pan5 to again raise the float.

The supply manifold consists of a tubular member 20 which is closed onboth ends and has a series of apertures 21 extending downwardly alongits lower side. This tube is in fluid receiving communication with thesupply conduit 16 and thus water discharges downwardly from each of theapertures 21'. An aperture is provided for each sheet and is disposedcentrally along the width thereof, as will appear. The tube 20 issecured by welding, for example, to a mounting plate 22, the centralpart of which is formed as an inverted V-shaped portion 23. The sideflanges 24-, 25 of the mounting plate are adapted to he slid intocomplementary groove members 26, 27, respectively, which together definea transversely extending slot 28 in the top of the duct. By simplywithdrawing the manifold axially from the grooves 26 and 27, themanifold can be completely removed for inspection, repair, or cleaningwhen necessary.

The sheet assembly PA consists of an upper plate support member in theform of a pan 3t) which has a corrugated bottom, the corrugationsextending longitudinally in the duct. In each of the lowermost portionsof these corrugations is a slot 31 through each of which a moistureabsorbent sheet 32 extends. The upper edges of these sheets are held inthe pan by means of the rod 33, one of which is located in each of thecorrugations and over which the absorbent and flexible sheets aretrained. The lower side of the sheet assembly is comprised of acollecting pan 5 which is rigidly secured to the upper pan by the fourcorner posts 36, providing an open framework. The lower end of theabsorbent sheets are supported in the collecting pan by means of theirrespective simply by pulling the snugly fitting clamping portions 40 oifthe collecting pan edges.

The collecting pan includes a threaded fitting -42 ex-- tendingdownwardly therefrom by means of which the conduit C can easily bedisconnected from the sheet assembly for quick removal of the latterfrom the duct.

The moisture absorbent flexible sheets 32 are shown for purposes ofillustration as being comprised of Turkish towel fabric formed as a loopand which loop passes over its respective pair of vertically alignedupper rods 33 and lower rods 37. The number of these sheets may bevaried, depending on the cubic footage of the building to be humidified,and, of course, the means of mounting or material used for these sheetsmay also be varied. With this particular unit, however, the entireassembly may be quickly removed from the duct and immersed in a cleaning fluid ior complete cleaning thereof.

It will be noticed that the cross-sectional area of the sheet assemblyis such that it substantially fills the crosssectional area of the ductto thereby insure complete coverage of the air passing thereby. Aspreviously mentioned, each aperture is located generally centrally ofthe width of its respective sheet, thereby insuring complete saturationacross the width of the sheet. The corrugations securely hold the rodsin proper spaced apart relationship, and furthermore act as distributingchannels I for distributing water all across the top edge of the sheets.

Resume T he action of the water being supplied to the sheets is suchthat even the uppermost portion and corners of the sheets are thoroughlysaturated. The moisture works its way downwardly over the sheets both bygravity and by capillary action, thereby insuring complete saturation ofthe entire sheet surface. fills to a predetermined level at which timethe float actuates the mercury switch to shut off further water supply.After the water has been shut oil, the sheets are maintained in a moistcondition by the capillary action of the water working its way backupwardly over the surface of flowing action of the Water along thesheets acts to flush any foreign material downwardly into the collectingpan, and the sheets are kept saturated and in a clean condition,

thereby contributing to a particularly eflicient evaporator unit.

The float chamber is completely separated from the collecting pan andthe only communication therewith is via the conduit C. The water in thefloat chamber remains unchanged and very little circulation between thewater in the float chamber and the collecting pan occurs. As a result,the water in the float chamber is maintained at a much coolertemperature than that in the collecting pan, and the water in the floatchamber is not being continually changed. This results in thesubstantial elimination of any lime deposits in the float chamber. Thus,the float can always act freely, and particularly the upwardly extendingrod 50 of the float can always pass freely through the guide tube 52which is secured to the cover of the float chamber.

The water supply valve is either completely on or com- Eventually, thecorrecting pan pletely closed and thereby the water is either beingadmitted full force to the manifold or not at all. There is nothrottling action on the water flow and no spraying or dripping ofwater. This positively acting valve is not subject to malfunctioning asis a needle-type valve found in other prior art devices.

Only the amount of water to be evaporated is fed to the unit and acontinually flowing and overflowing water supply is eliminated. Thepresent humidifier requires no overflow conduit or drains for excesswater.

The sheet assembly can easily be removed by simply disconnecting thecoupling 43 of the conduit C, and sliding the assembly horizontally outthe opened door, the fitting 42 sliding in the open-ended slot 42:: inthe bottom of the duct. It can then be completely cleaned or repairedwhen necessary.

With the present invention, a humidistat is not necessary to control thehumidity, although one may be supplied as optional equipment, ifdesired. However, the present humidifier is sized according to the cubicfootage in the building to be humidified. For example, in a 10,000 cubicfoot home, for a desirable six changes of air per hour and for a maximumrelative humidity of 45 percent at an outside temperature of 30 abovezero, about seven evaporator sheets of the type described and of a sizeabout 7 inches by 8 /2 inches, would be suitable.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

I claim:

1. A humidifier unit comprising, an air passage duct, a series ofgenerally vertically disposed and moisture :absorbent evaporator sheetsin said duct whereby air passing through said duct will pass said sheetsto pick up moisture therefrom, water supply means adjacent an upperportion of said duct and adapted to supply water to said sheets adjacentthe upper portions thereof whereby said water will flow downwardly oversaid plates, a water collecting pan at the bottom portions of saidsheets and in which the latter are located whereby the water in said panmay be drawn upwardly by said sheets due to capillary action thereof, anon-oii water valve for said water supply means, actuating means for saidwater valve and mounted on the outside of said duct, and a floatmechanism including a float chamber mounted on the outside of said ductand having a detachable conduit connection with said collecting panwhich places the latter in water communication with said chamber, saidconduit connection being located beneath both the chamber and thecollecting pan, said mechanism also including a float in said chamberand engageable with said actuating means for causing operation thereof,whereby when the water level in said collecting pan rises above apredetermined level, said float will cause operation of said actuatingmeans to shut off said water valve.

2. A humidifier unit comprising, an air passage duct, a closable door insaid duct, an evaporator sheet assembly removably mounted in said airduct whereby air passing through said duct will pass through saidassembly to pick up moisture therefrom, said assembly being removablefrom said duct through said door; said assembly comprising, an upper panand a lower collecting pan secured together as a unit, a plurality ofgenerally vertically disposed moisture absorbent evaporator sheetsextending between said pans, said sheets having an upper portion locatedin said upper pan for receiving water, and said sheets having lowerportions located in said lower collecting pan whereby water movingdownwardly over said sheets is collected in said lower pan and then canbe pulled upwardly by capillary action of said sheets; water supplymeans adjacent an upper portion of said duct and adapted to supply waterto said upper portions of said sheets whereby said water will flowdownwardly over said sheets; and operating means including a floatmechanism located outside said duct and for operating said water supplymeans, conduit means placing said collecting pan in water communicationwith said float mechanism, and a disconnect coupling in said conduit topermit complete removal of said assembly through said door.

3. An evaporator sheet assembly for a humidifier and adapted to beinserted directly in and removable from the air passage of an air duct,said assembly comprising, substantially horizontally disposed upper andlower pans secured together as a unit, a plurality of generallyvertically disposed moisture absorbent evaporator sheets extendingbetween said pans, said sheets each comprising an endless loop, saidupper pan having a series of parallel corrugations in its bottom, a slotin the lower part of each of said corrugations and through which anupper portion of a corresponding loop extends into said upper pan forreceiving water therefrom, a rod located in each of said corrugationsand extending through said upper portions of a corresponding loop toretain the latter in said upper pan, and said sheets having a lowerportion located in said lower pan, means for holding said lower portionsin said pan and maintaining said loops taut, whereby water movingdownwardly over said sheets is collected in said lower pan and then canthe pulled upwardly by capillary action of said sheets.

References Cited in the file ofthis patent UNITED STATES PATENTS 246,781Jennings Sept. 9, 1881 872,330 Cunningham Dec. 3, 1907 1,132,679 Murrayet al. Mar. 23, 1915 1,367,701 Haynes Feb. 8, 1915 1,418,296 GohmannJune 6, 1922 1,928,912 Scherer et al. Oct. 3, 1933 1,962,532 Strong June12, 1934 1,983,294 Huttenmiller Dec. 4, 1934 2,158,543 Jensen May 16,1939 2,268,540 Andrews Jan. 6, 1942 2,285,725 Kneedler June 9, 19422,303,948 Morris Dec. 1, 1942 2,804,067 Elgin Aug. 27, 1957 3,033,193Rathman May 8, 1962 FOREIGN PATENTS 464,147 France Oct. 27, 1913 127,977Great Britain June 10, 1919

1. A HUMIDIFIER UNIT COMPRISING, AN AIR PASSAGE DUCT, A SERIES OFGENERALLY VERTICALLY DISPOSED AND MOISTURE ABSORBENT EVAPORATOR SHEETSIN SAID DUCT WHEREBY AIR PASSING THROUGH SAID DUCT WILL PASS SAID SHEETSTO PICK UP MOISTURE THEREFROM, WATER SUPPLY MEANS ADJACENT AN UPPERPORTION OF SAID DUCT AND ADAPTED TO SUPPLY WATER TO SAID SHEETS ADJACENTTHE UPPER PORTIONS THEREOF WHEREBY SAID WATER WILL FLOW DOWNWARDLY OVERSAID PLATES, A WATER COLLECTING PAN AT THE BOTTOM PORTIONS OF SAIDSHEETS AND IN WHICH THE LATTER ARE LOCATED WHEREBY THE WATER IN SAID PANMAY BE DRAWN UPWARDLY BY SAID SHEETS DUE TO CAPILLARY ACTION THEREOF, ANON-OFF WATER VALVE FOR SAID WATER SUPPLY MEANS, ACTUATING MEANS FOR SAIDWATER VALVE AND MOUNTED ON THE OUTSIDE OF SAID DUCT, AND A FLOATMECHANISM INCLUDING A FLOAT CHAMBER MOUNTED ON THE OUTSIDE OF SAID DUCTAND HAVING A DETACHABLE CONDUIT CONNECTION WITH SAID COLLECTING PANWHICH PLACES THE LATTER IN WATER COMMUNICATION WITH SAID CHAMBER, SAIDCONDUIT CONNECTION BEING LOCATED BENEATH BOTH THE CHAMBER AND THECOLLECTING PAN, SAID MECHANISM ALSO INCLUDING A FLOAT IN SAID CHAMBERAND ENGAGEABLE WITH SAID ACTUATING MEANS FOR CAUSING OPERATION THEREOF,WHEREBY WHEN THE WATER LEVEL IN SAID COLLECTING PAN RISES ABOVE APREDETERMINED LEVEL, SAID FLOAT WILL CAUSE OPERATION OF SAID ACTUATINGMEANS TO SHUT OFF SAID WATER VALVE.